Biodegradation of Petroleum Hydrocarbon by Pseudomonas Aeruginosa

A bacterial strain of the genus Pseudomonas aeruginosa was inoculated into a hydrocarbon culture medium and incubated for a definite period of time. The ability of the bacterial strain to biodegrade a hydrocarbon, viz. n-hexadecane, was evaluated through determining the hexadecane concentration in the inoculated culture medium on a gas chromatograph (GC). The effect of pH value on the degrading ability of the bacterial isolate and the impact of temperature on microbial growth were also explored. Test results showed that Pseudomonas aeruginosa was markedly effective in biodegrading n-hexadecane. Furthermore, the ability of Pseudomonas aeruginosa to biodegrade n-hexadecane was different at various pH values. Pseudomonas aeruginosa provided excellent degrading ability at a pH value of 7.0. The microbial cells of Pseudomonas aeruginosa increased with an increasing incubation duration at temperatures ranging from 28 ℃ to 35 ℃, and an exponential phase of microbial growth was observed.     

无机盐作用下微波辐射高粘度原油的油水分离

Removal of water contained in extra-viscous crude oil is quite difficult because of the high viscosity and high resins content of heavy oil.The microwave technology was introduced for the separation of water from high-viscosity crude oil in the presence of sodium acetate.The decrease in zeta-potential of interface and the viscosity of crude oil are responsible for the accelerated separation of water under microwave irradiation.The influences of the concentration of sodium acetate in sample,irradiation pressure,irradiation time and irradiation power on the separation efficiency were investigated.The optimum technological condition for the refining process was determined.Upon treating the sample 1 (with a water concentration of 50%),the water removal rate was 98.44%,when the optimum conditions were identified to be a sodium acetate concentration of 2%,an irradiation pressure of 0.1 MPa,an irradiation time of 2 min,and an irradiation power of 225 W,with the recovery of sodium acetate reaching 97.88%.Upon treating the sample 2 (the concentration of water was 20%),the water removal rate was 93.85%,when the optimum conditions were determined to be a sodium acetate concentration of 3%,an irradiation pressure of 0.1 MPa,an irradiation time of 4 min,and an irradiation power of 375 W,with the recovery of sodium acetate reaching 93.54%.By using this method,the dehydration efficiency was increased rapidly.     

Characterization and optimization of EPS-producing and diesel oil-degrading Ochrobactrum anthropi MP3 isolated from refinery wastewater

Petroleum refinery wastewater （PRW） containing hydrocarbon is highly toxic to the environment and the surrounding ecosystem. Proper treatment of the PRW effluent is necessary to remove the pollutants before discharge. Bioremediation is considered to be a promising approach as it is eco- friendly and efficient. The exopolysaccharide （EPS） produced by the O. anthropi acts as a bioemulsifier and showed the highest emulsification activity of 60% on diesel. An EPS yield of about 0.42 g/L was obtained under optimized conditions. The carbohydrate and protein content of the EPS was found to be 71.1% and 19.7% respectively, showing the glycoprotein nature. The structural properties of EPS were analyzed by FT-IR and 1H NMR. The batch degradation of oil in PRW by O. anthropi was studied gravimetrically, and showed about 53% degradation in 7 days, indicating the strong ability of the isolated strain to degrade the hydrocarbons in PRW.     

Laccase Immobilized on Mesoporous Silica Materials and Its Corrosion Inhibition Performance in Circulating Cooling Water System

Mesoporous SiO_2 microspheres were synthesized using the sol-gel method and were characterized by TEM, FT-IR and BET techniques. The diameter of the microspheres is about 100—150 nm, and the average mesopore diameter is 2.55 nm, while the specific surface area is 1 088.9 m2/g. Mesoporous SiO_2 microspheres adsorb glutaraldehyde and immobilize laccase by means of the aldehyde group in glutaral which can react with the amidogen of laccase. The immobilization conditions were optimized at a glutaraldehyde concentration of 0.75%, a crosslinking time of 8 h, a laccase concentration of 0.04 L/L and an immobilization time of 10 h. When diesel leakage concentration was 80 mg/L, the highest corrosion inhibition efficiency of immobilized laccase reached 49.23%, which was slightly lower than the corrosion inhibition efficiency of free laccase(59%). The diesel degradation ratio could reach up to 45%. It has been proved that the immobilized laccase could degrade diesel to inhibit corrosion.     

Optimization of safflower oil transesterification using the Taguchi approach

Biodiesel is an alternative renewable fuel which is produced by using biomass resources. Its physicochemical properties are close to those of the petroleum diesel fuel. This study highlights biodiesel production from safflower seed oil. The main aim of this experimental work is to optimize the process parameters, namely the methanolto-oil molar ratio, catalyst concentration, reaction time and reaction temperature for biodiesel production. The Taguchi robust design approach was used with an L9 orthogonal array to analyze the influence of process factors on performance parameters. The results showed that the optimum yield of biodiesel was 93.8% with viscosity 5.60 c St, with a methanol-to-oil molar ratio of 4:1, catalyst concentration of 1.5 wt%, reaction time of 90 min and reaction temperature of 60 ℃. The catalyst concentration was found to be the most influencing parameter which contributed 51.1% and 50.8% of the total effect on the yield of biodiesel, Y_1, and viscosity of biodiesel, Y_2, respectively.     

Application of Microwave Technology for Desulfurization of Diesel Fuel

The microwave technology was introduced for the desulfurization of diesel fuel. The atmospheric second side-cut diesel fraction, which was supplied by Liaohe Petrochemical Company, was desulfurized by an oxidation process under microwave irradiation. Hydrogen peroxide (H202), can oxidize the sulfur compounds in diesel fuel selectively and convert them into sulfones. Based on the rule of dissolution by similar substances,these sulfones are removed from diesel fuel because they could be dissolved in solvent phase. So the sulfur content of diesel fuel is decreased. The influence of the concentration of oxidizing reagent, solvent phase to oil phase volume ratio (S/O), irradiation pressure, irradiation time, and the irradiation power have been investigated.The optimum conditions for the refining process was determined. The sulfur removal rate was 59.7% under the optimum conditions of 8%H2O2, S/O=0.25, 0.05MPa, 6 min, and 375W, respectively. When no microwave irradiation was applied, the removal rate was 11.5% only.     

Degradation of diphenyl chlorophosphate by using ozone

Diphenyl chlorophosphate （DPCP）, which acts as a simulant of nerve warfare agent, is decontaminated by ozone in this study. Experimental results show that DPCP can be degraded rapidly by ozone. In the optimum working conditions, 99% 50 mg/L DPCP are degraded in 16min, and 30% total organic carbon of the solution is reduced. The free radical accelerant, Fe2＋, and inhibitors, 2-propanol and tert-butanol significantly influence the degradation efficiency of DPCP, therefore, free radical is the most important oxidant for the DPCP degradation reaction in this system. Ozone can be decomposed to hydroxyl radical, which would attack DPCP to start the degradation reaction. Furthermore, parts of DPCP would be mineralized, and degradation of toluene probably is the controlling step of the mineralization of DPCP. Finally, the reaction pathways are predicted for the degradation of DPCP by ozone.     

基于主成分分析法和响应曲面法对Halomonas菌株生长因子的分析与优化

The biomass of petroleum-degrading bacteria, such as Halomonas spp., is crucial to the alleviation of severe oil spills through bioremediation. In this paper, the bacterium (HDMP1) was isolated and identified. Growth factors were analysed and optimised through the single-factor experiments, the factor analysis (FA), the principal component analysis (PCA), and the response surface methodology (RSM). Results indicated that HDMP1 was identified as genus Halomonas. In the single-factor experiments, the range of suitable growth conditions for HDMP1 covered: a salt concentration of 2%-4%, a medium pH value of approximately 9, an inoculum concentration of 1.0%, a substrate concentration of 1.0%-1.4%, and a rotation rate of 140 r/min. The evaluation by FA and PCA indicated that three significant growth factors were the salt concentration, the pH value, and the rotation rate. A maximum biomass of HDMP1 was obtained under the conditions covering a salt concentration of 3.5%, a medium pH of 8, and a rotation rate of 151 r/min by optimization.     

Incised valley filling deposits: an important pathway system for long-distance hydrocarbon migration—a case study of the Fulaerji Oilfield in the Songliao Basin

In this paper, incised valley filling deposits, which formed an important pathway system for long-distance hydrocarbon migration, are discussed in detail based on core and logging data. The sequence SQy23 of the Cretaceous Yaojia Formation is the main hydrocarbon-bearing layer in the Fulaerji Oilfield. The hydrocarbon source of the oilfield is the Qijia-Gulong Sag which is about 80 km away from the Fulaerji Oilfield. The transport layer of long-distance hydrocarbon migration is the overlapped sandstone complex which fills the incised valley. The incised valley developed during the depositional period from the late Qingshankou Formation to the early Yaojia Formation of Cretaceous （SQqna-SQy0 was about 70 km long and 20 km wide, and extended in the NW-SE direction. The overlapped filling of the incised valley mainly occurred in the expanding system tract of the third-order sequence SQy23 （ESTy23）. Towards the basin, incised valley filling deposits overlapped on the delta developed in the early period, and towards the basin margin, incised valley filling deposits were covered by the shore-shallow lacustrine sandy beach bar developed in the maximum flooding period. All of the delta, the incised valley filling and the shore-shallow sandy beach bar are sandstone-rich, and have high porosity and permeability, and can form an effective hydrocarbon migration and accumulation system. Deltaic sand bodies collected and pumped hydrocarbon from the active source, incised valley filling depositional system completed the long-distance hydrocarbon migration, and lithological traps of shore-shallow lacustrine sandy beach bar accumulated hydrocarbon. The incised valley filling sequences are multi-cycle： an integrated shortterm filling cycle was developed on the erosion surface, and the sequences upward were mud-gravel stone, medium-fine sandstone containing terrigenous gravels and muddy pebbles with cross bedding, silty mudstone with ripple bedding, and mudstone. The incised valley filling deposits are characterized by a strong heterogeneity and the main hydrocarbon migration pathway is the medium-fine sandstone interval.     

加氢苛刻度对烃类组成和催化裂解产品分布的影响

Residue deep hydrotreating (RDHT) process was developed by the Research Institute of Petroleum Processing (RIPP) to provide high quality feedstock for deep catalytic cracking (DCC) process. In this research work, the effects of RDHT process and reaction severity on heteroatom removal, hydrogen content increase, hydrocarbon composition improvement, and DCC product yields were studied. It was showed that the RDHT process can effectively reduce heteroatoms, increase hydrogen content and improve the hydrocarbon compositions, which can contribute to an increase of light olefins yield in DCC unit.     

石油污染土壤生物修复高效菌的降解特性

 研究了从陕北石油污染土壤中分离的7株菌SY21、SY22、SY23、SY24、SY42、SY43和SY44的生长特性及其对不同烃类的利用能力及除油影响因素。结果表明,受试细菌的生物除油率高,培养13 23h后的活性最高,易于扩大培养;分离菌株均能在石蜡培养基中生长,表明对中长链的烷烃降解能力高,其中菌株SY22、SY23、SY24、SY42和SY43均能利用几种不同的烃类生长,是土壤生物修复的优选菌株。菌株SY22 和SY23最适pH为9.0,菌株SY21 和SY42最适pH为7.0;污染强度为1000 1500mg/L、氮源为硝酸铵时,石油烃的降解率最佳;对具有PAH降解能力的SY22、SY42和SY23菌株而言,添加淀粉和葡萄糖为碳源提高了菌株对原油的降解率。土壤中Fe2+、Mn2+的存在对细菌降解石油烃影响不大,但Ni2+、Co2+金属离子会降低分离菌株的除油能力。     

生物强化技术在油田污水处理工程中的应用

随着三次采油技术的发展,油田污水的处理难度逐步增大。本文针对河南油田采出水,研究了石油磺酸盐对现场高效降解菌生长量的影响,定性分析了污水中的聚合物。结果表明,石油磺酸盐对3种降解菌的抑制作用从大到小依次为：W菌、I菌、B菌,污水中石油磺酸盐浓度应小于20 mg/L,以确保微生物的生长代谢;污水中聚丙烯酰胺的分子结构发生了一定的变化,—CONH2水解为—COOH。通过室内实验,选择尿素和有机营养制剂作为氮源,最佳用量分别为10.71和8.57 mg/L。污水处理系统启动过程中,加入尿素、有机营养制剂和天然有机营养制剂,运行25 d后的外排水各项指标均达到国家标准。图5表3参8     

热解参数S1的轻烃与重烃校正及其意义——以渤海湾盆地大民屯凹陷E2s4(2)段为例

利用热解参数S₁（游离烃含量）对页岩油进行资源评价时存在轻烃和重烃损失的现象,导致计算资源量偏小。针对重烃损失,将相同泥页岩样品经抽提前、后热解实验所得的S₂（热解含量）进行对比,二者之差即为S₁损失的重烃含量。针对轻烃损失,基于未熟泥页岩样品Rock-Eval和PY-GC实验以及对原油进行的金管实验,根据化学动力学原理求取各动力学参数,结合Easy R_o模型计算出不同成熟度时生成的C_6-13与C₁₃₊的比值,将此值作为烃源岩内残留的C_6-13与C₁₃₊比值,并在经重烃恢复之后的S₁基础上进行轻烃恢复。使用轻烃与重烃恢复前、后的S₁作为页岩油资源评价参数,在资源量计算方面差别较大。以渤海湾盆地大民屯凹陷E₂s^4（2）段为例,其恢复前资源量为2.26×10⁸t,恢复后资源量为6.47×10⁸t,恢复后资源量为恢复前的2.86倍。因此在利用S₁对页岩油进行资源评价时,对S₁的轻烃和重烃恢复具有重要意义。     

湄洲湾海洋细菌降解石油烃研究

研究了从湄洲湾海域分离的两个菌株HI和H2对石油的降解作用。实验测定了在5个不同源油初始浓度下的原油降解率,并考察了在原油初始浓度3000mg/l,6d的培养过程中,培养液的OD值及原油降解率的变化。分别以正十一烷,正十六烷,正二十四烷,萘和菲5种纯烃配制成3种混合烃养基,以考察两个菌株对芳烃及烷烃的降解能力。结果表明,两个菌株对烷烃和芳烃都有较高的降解速度和耐油性,但对底物的利用和对含N,P营养盐的要求有显著的不同,H1菌株不需要营养盐,对芳香烃降解特别有效;而H2菌株需要营养盐,对烷烃的降解较为有效。     

一株磺化沥青降解菌的筛选鉴定及降解特性研究

为了选育降解磺化钻井液的微生物菌株,以新疆克拉玛依油田磺化钻井液污泥为微生物菌源,磺化沥青为唯一碳源,进行富集、驯化、分离纯化等筛选有效降解磺化沥青的菌株,经生理生化及分子生物技术鉴定种名,单因素实验和正交实验研究降解特性。结果获得一株有效降解磺化沥青的菌株,命名为X2,生理生化与分子鉴定为大洋沉积物芽孢杆菌。单因素实验表明,X2生长最佳的P源为KH₂PO₄,N源为NH₄NO₃;正交实验结果显示,X2菌体最佳生长条件为温度为36℃、pH值为7.8、盐浓度为1%、接种量为10%;COD降解最佳条件为36℃、pH值为8.2、盐浓度为0.9%、接种量为12%,降解率为59%~71%;pH值的R极差最大,是同时影响菌株生长及COD降解的关键因子。实验结果为降解钻井废液COD提供了有效的理论基础。      

基于全二维气相色谱的原油C_8轻烃新参数

C_5—C_(13)轻烃馏分是原油的重要组分,对于C_8以上轻烃组分的研究一直处于比较薄弱的状态。对塔里木盆地哈拉哈塘凹陷11件典型的奥陶系海相原油样品及北部湾盆地福山凹陷流沙港组流三段8件典型的古近系陆相原油样品进行了全二维气相色谱(GC×GC)和色谱/质谱(GC-MS)对比分析。借助标准样品并结合相关文献资料,对原油C_8轻烃组分中31个化合物进行了定性定量分析,发现原油C_8轻烃馏分中三甲基环己烷和三甲基环戊烷丰度较高。其中:顺-1,3-二甲基环己烷(c,1,3-DMCYC_6)、反-1,4-二甲基环己烷(t,1,4-DMCYC_6)和1,1-二甲基环己烷(1,1-DMCYC_6)相对丰度始终保持固定的比例,比值接近4∶2∶1;顺-1,反-2,顺-4-三甲基环戊烷(ctc,1,2,4-TMCYC_5)和顺-1,反-2,顺-3-三甲基环戊烷(ctc,1,2,3-TMCYC_5)也保持着1∶1的近似比值。并推测二甲基环己烷与甲基环己烷、三甲基环戊烷与二甲基环戊烷可能有着相似的母源输入。在此基础之上,针对C_8中的单体化合物建立了C_8轻烃新参数——轻烃比LHR。LHR为反-1,4-二甲基环己烷+顺-1,3-二甲基环己烷+1,1-二甲基环己烷与顺-1,反-2,顺-4-三甲基环戊烷+顺-1,反-2,顺-3-三甲基环戊烷的丰度比值,即(t,1,4-+c,1,3-+1,1-)DMCYC_6/(ctc,1,2,4-+1,2,3-)TMCYC_5。研究表明,LHR与经典沉积环境参数Pr/Ph,C_(21)/C_(23)TT及DBT/P线性关系良好,可以有效地用于表征原油或源岩有机质来源。     

排烃机理及厚度探讨

为研究排烃,苏北盆地建立了4条地球化学剖面。根据剖面源岩在排出路线上未反映出烃浓度的梯度变化,以及各处源岩仍保持原有地球化学特征等说明微孔道排烃的假说不成立。研究表明,层段之间存在异常压力释放及排烃的不均衡,这种不均衡与层段之间的生烃能力差异有密切关系。根据泥岩中观察到的大量微裂隙和层段间的排烃差异,提出烃类排出是一个从压力积聚到压力释放的幕式涌流过程,通过生烃达到地层增压、形成层面破裂和纵向微裂隙,然后排出。微裂隙排烃具有"优势生烃者先排烃、段与段之间差异为主、无厚度限制"三大特点。     

The Isolation of Bioflocculant-producing Strains and the Application in the Oily Wastewater Treatment Process

Three bioflocculant-producing bacteria strains were isolated by the pyridine screening method. The flocculating rate of bioflocculant produced by KL9-1-3 on kaolin suspension (4.0g/L) reached as high as 98.2%. The strain KL9-1-3 was identified as Rhodococcus sp. according to its morphological, physiological, biochemical, and 16S rDNA sequence characteristics. It was deduced that the main component of purified bioflocculant was polysaccharide through infrared spectrophotometry and GC-MS analysis. The bioflocculant KL9-1-3 can effectively deal with oily wastewater, and the corresponding maximum removal rates of oil and COD for oily wastewater were 74.1% and 42.9%, respectively, under the optimum conditions of bioflocculant dosage 0.2 mL/L, pH 10.0, temperature 40°C, and Ca²⁺ as the coagulant.     

固定化微生物应用于生物修复石油污染土壤

 从石油污染土样中筛选和纯化了2株降解石油污染物的高效微生物菌株H和F，以它们为生物活性物质，采用生物大分子仿生合成出的纳米多孔SiO₂为载体，通过表面吸附固定化方法将其固定，制备出固定化微生物。将固定化微生物应用于含有石油污染物土壤的生物修复。结果表明，该固定化微生物对石油污染物50h一次降解率高达96.2%；通过8次的反复实验，50h的原油降解效果保持在85%以上。